16 Million Different Colors
The combination of Red, Green and Blue values from 0 to 255 gives a total of more than 16 million different colors to play with (256 x 256 x 256). Most modern monitors are capable of displaying at least 16,384 different colors. To assist you in using color schemes, check out http://wellstyled.com/tools/colorscheme2/index-en.html. This site lets you test different color schemes for page backgrounds, text and links.